Vehicle mirrors which are mounted to extend a substantial distance beyond the lateral limits of the vehicle on which they are mounted are frequently susceptible to damage as they may be brought into accidental engagement with building walls or other extraneous obstacles. Accordingly, it is common to build the mirror supporting framework of a first bracket which is rigidly connected to the vehicle body, generally on the side of the cab, and a second bracket member which carries the mirror itself and is pivotally connected on a generally upright axis to the first bracket member for folding movement to an inner or collapsed position when a fixed obstacle is contacted.
Many of these mirrors are provided with ratchet type pivot mechanism such as by facing series circumferentially spaced interlocking teeth which yieldably lock the mirror in an adjusted position but which upon forcible contact permit collapse without damaging the supporting frame. Examples of such mirror support mechanisms are shown in U.S. Pat. Nos. 2,488,316 and No. 2,969,715, both to Mosby; No. 1,676,896 to Groenenstein; No. 1,921,310 to Crisma; and No. 2,701,113 to Koonter.
While the aforementioned structures do permit the desired folding of the mirror frame to a collapsed condition the structures involved are either expensive to manufacture or do not provide maximum surface area locking engagement between the interlocking teeth surfaces involved.